Board Foot Calculator

Easily calculate lumber volume and cost for your woodworking projects.

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Your Project Totals

Total Board Feet

0.00

Required with Waste

0.00

Estimated Cost

$0

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About the Board Foot Calculator

A board foot is the standard unit of volume for lumber in North America. This calculator helps woodworkers, carpenters, and DIY enthusiasts quickly determine the total board feet for their projects, making it easy to purchase the right amount of lumber and estimate costs accurately.

Formula Explained

The calculation for board feet is straightforward. Our tool handles all the math, including converting fractional thickness values into decimals for an accurate result.

(Thickness (in) × Width (in) × Length (ft)) / 12

The total cost is calculated by multiplying the final board feet (including the waste factor) by your price per board foot.

How to Get Better Results

For the most accurate lumber estimate, consider these tips:

Use Nominal Thickness

Board feet are typically calculated using the nominal (rough-sawn) thickness, not the actual (planed) thickness. For example, a "1-inch" thick board is often 3/4" thick, but you should calculate it as 1 inch.

Include a Waste Factor

Always add a waste factor (10-20% is common) to account for cuts, knots, and mistakes. It's better to have a little extra lumber than to run out mid-project.

Frequently Asked Questions

What is a board foot?

A board foot is a unit of volume for lumber, representing a piece of wood that is 12 inches long, 12 inches wide, and 1 inch thick. It's the standard measurement used in the United States and Canada for pricing and selling hardwood lumber.

How is this different from linear feet?

Linear feet is a measure of length only. Board feet is a measure of volume, which accounts for the thickness and width of the lumber as well. Hardwoods are almost always sold by the board foot, while softwoods (like pine 2x4s) are often sold by the linear foot.

Why is the formula divided by 12?

The formula is divided by 12 because the length is measured in feet while the thickness and width are measured in inches. This division converts the inches part of the calculation into feet, resulting in the correct board foot volume.